Fabrication of YSZ electrolyte for intermediate temperature solid oxide fuel cell using electrostatic spray deposition: II – Cell performance

Abstract

Electrostatic spray deposition (ESD) was applied to fabricate a thin-layer of yttria-stabilized zirconia (YSZ) electrolyte on a solid oxide fuel cell (SOFC) anode substrate consisting of nickel-YSZ cermet. A colloidal solution of 8 mol% YSZ in ethanol was sprayed onto the substrate anode surface at 250–300 °C by ESD. After sintering the deposited layer at 1250–1400 °C for 1–2 h depending on temperature, the cathode layer, consisting of lanthanum strontium manganate (LSM), was sprayed or brush coated onto the electrolyte layer. Performance tests and AC impedance measurements of the complete cell were carried out at 800 °C to evaluate the density and conductance of the electrolyte layer formed by ESD. With a 97% H2/3% H2O mixture and air as fuel and oxidant gas, respectively, the open-circuit voltage (OCV) was close to theoretical and electrolyte impedance was about 0.23Ω cm2. A power density of 0.45 W cm−2 at 0.62 V was obtained. No abnormal degradation was observed after 170 h operation. The electrolyte sintering temperature and time did not significantly affect the electrolyte impedance.